Cable release for fire protection system and the like



g- 2 9 H. J. FLAJOLE ETAL 3,463,236

CABLE RELEASE FQR FIRE PROTECTION SYSTEM AND THE LIKE Filed Dec. 5, 1967 2 Sheets-Sheet 1 F3}; INVENTORS F l HENRY J. FLAJOLE" FRED R. ANDERSEN BY onus .4. moupsou A T OPNEYS g- 1969 H. J. FLAJOYLE ETAL 3,463,236

CABLE RELEASE FOR FIRE PROTECTION SYSTEM AND THE LIKE Filed Dec. 5, 1967 2 Sheets-Sheet 2 INVENTORS HENRY J'. FLAJOLE FRED R. ANDERSEN BY DALE A. THOMPSON F 5 /%%ZM&

United States Patent 3,463,236 (TABLE RELEASE FOR FIRE PROTECTION SYSTEM AND THE LIKE Henry J. Flajole, Fred R. Andersen, and Dale A. Thompson, Menominee, Mich., assignors to The Ansul Company, Marinette, Wis., a corporation of Wisconsin Filed Dec. 5, 1967, Ser. No. 688,041 Int. Cl. A62c 37/30, 37/02 US. Cl. 169-42 Claims ABSTRACT OF THE DISCLOSURE This invention relates to hazardous condition protection systems and, more particularly, to a remote cable release mechanism for such systems. While not limited thereto, the invention is particularly applicable to fire extinguishing systems.

In a fire protection system, it is often desirable to permanently install the fire extinguishers throughout the protected area and to control the individual extinguish ers from a central control unit. With a water sprinkler system, for example, the sprinkling nozzles can be distributed throughout the protected area and controlled by means of a main valve at a common control unit. With respect to the dry chemical extinguisher systems, one or more dry chemical tanks and associated nozzles can be located to protect the desired area and activated by a main high-pressure CO cartridge coupled to the individual extinguisher units.

Preferably, the sensor units for detecting fire or hazardous conditions should be carefully located to provide complete protection and to best sense the hazardous conditions. The locations for the sensing units may or may not correspond to the location of the extinguishers. Also, the number of sensing devices may or may not correspond to the number of extinguisher units.

Thus, an object of this invention is to provide a flexible actuating arrangement where the number of extinguishers and the location of the same is independent of the number and location of sensing units.

Another object is to provide an actuating arrangement wherein a plurality of sensors can be easily and conveniently coupled to a common control unit of the protection system.

Another object is to provide a highly reliable actuating arrangement including series connectible fusible links which can easily be installed, set up, and aligned for proper operation.

Still another object is to provide an actuating cable release system with multiple sensing devices such that the cable tensioning mechanism can be located at the control unit.

Prior to this invention, cable release mechanisms employing fusible links were known. With these prior systerns, the release cable would be broken at one or more locations with the free ends of the cable being attached to the ends of fusible links inserted at the breaks. Considerable ditficulty has been experienced with these prior systems, however, because of the difiiculty in accurately locating the breaks in the cable to correspond to the de- 3,463,236 Patented Aug. 26, 1969 sired locations for the fusible links, as well as the difiiculty in inserting suitable couplings at the free ends of the cable. Also, with the prior systems, the release cable would be completely severed in one or more locations upon occurrence of a fire making it diflicult to reset, or realign, the system, since it would often be necessary to completely rethread the cable, and, in some cases, readjust the cable lengths.

Parallel cable systems have also been employed in the past where, in effect, each fusible link would be coupled to the common control unit by a separate cable. While succcessful, such systems are also difiicult to install and align in a manner which provides assurance that each cable will operate independently. The parallel systems also have the undesirable requirement that the tensioning mechanisms be located remote from the common control unit.

In the system according to this invention, .a continuous unbroken cable is utilized in the release mechanism. Loops are formed and maintained in the cable at the location of the sensors. Upon detection of a fire or other hazardous conditions, the cable loop is released and the resulting slack of the cable in turn actuates the common control unit. Since there are no breaks in the cable, the system is easily installed and readily reset after occurrence of a fire or the like.

The invention is described in more detail in the following specification in which an illustrative embodiment of the invention is set forth. The drawings form part of the specification wherein:

FIGURE 1 is a plan view, with certain portions broken away, illustrating a common control unit and a pair of detector units interconnected by a release cable;

FIGURE 1A is a side view illustrating the tensioning mechanism for the release cable;

FIGURE 2 is a side view illustrating one of the detector units in the normal condition;

FIGURE 3 is a side view of the terminal detector unit at the end of the release cable in its normal condition;

FIGURE 4 is a side view showing a detector unit after separation of the fusible link; and

FIGURE 5 is a perspective view illustrating a fusible link.

A control unit 10 is shown in FIGURE 1, including an actuating lever 11 and the tensioning mechanism 12 secured to the end of a continuous release cable 14. The cable passes through a suitable conduit structure 15 and around hinged units 16 and 17 which form loops 18 and 19, respectively, in the cable. An actual installation can include as many hinged units as is desirable since, as will be explained, release of any one of the loops in the cable is sufiicient to actuate the control unit.

The hinged unit 16 ('best seen in FIGURE 2) includes a center pivot 20 and a pair of leaves 21, 22, each of an offset configuration and joined to the pivot. A curved cable guide sleeve 23 is fastened near the free end of binge leaf 21 and a similar guide sleeve 24 is fastened near the free end of hinge leaf 22. Suitable guide slots 25 and 26 are provided at the bend in the respective leaves near the pivot to stabilize the contact between the cable and the hinge leaves. The cable 14 slides through the guide sleeves and passes around the pivot portion of the hinge so that when the hinged unit is in the latched condition, as shown in FIGURE 2, the loop 18 is formed in the cable.

A fusible link 29 is illustrated in FIGURE 5 and includes a pair of similiarly dimensioned plates 30 and 31. Plate 30 is secured to an eyelet 32 and plate 31 is similarly secured to a eyelet 33. The plates are joined together by suitable heat sensitive material such as solder at connection points 34. When the ambient temperature exceeds a predetermined value, the heat sensitive material melts and the plates and eyelets separate.

A pair of books 36 and 37 (FIGURE 2) are riveted to the lower sides of the hinge leaf end portions. Hook 36 secured to leaf 21 is elongated so that one eyelet of the fusible link can slide over the free end of the hook and then pivot into position. The hook 37 attached to the other leaf of the hinge includes a lip 38 dimensioned so that the other eyelet of the fusible link can slide over the lip and latch the hinged unit as shown in FIGURE 2.

The function of fusible link 29 is to limit the separation between the leaves of the hinge to thereby maintain cable loop 18 under normal conditions. The fusible link, as shown in FIGURE 5, is of a relatively simple structure, but more elaborate and sophisticated fusible linke structures can be employed where desired or necessary. Also, other types of sensors can be employed which include a pair of eyelets provided the unit is designed to limit the separation between the eyelets except when certain hazardous conditions such as shock, infrared radiation, etc., are detected.

A generally U-shaped bracket 40 includes threaded apertures in the legs 39 and is coupled to the conduit by means of conventional conduit fittings 41. Cable 14 enters and leaves the area of the hinged unit through these apertures and, hence, these apertures position the cable relative to the bracket. The bracket includes a recess 42 in the center portion to assist in positioning the hinged unit. The cable loosely slides through guide sleeves 23 and 24 and the hinged unit is therefore easily centered within tthe bracket. When the hinged unit is latched by fusible link 29, and cable 14 is tensioned, the hinged unit is urged into the recess 42 thereby tending to maintain the hinged unit in the desired centered position. By so maintaining the hinged unit in its centered position, the possibility of a hang-up is minimized when the fusible link separates.

The terminal detector unit, i.e., the unit most distant from the control unit, is shown in FIGURE 3. This unit is similar in structure to the other detector units illustrated in FIGURE 2 and, hence, similar reference numerals are employed where applicable. One of the threaded apertures of bracket 40 is not coupled to the conduit, but instead, is coupled to a terminal clamping lug 44. The terminal clamping lug is secured in the threaded opening and includes a small central passage for cable 14. A pair of set screws 45 are arranged to secure the end of cable 14 in the clamping lug.

Referring to FIGURE 1, it can be seen that release cable 14 is anchored at one end by clamping lug 44 and then passes around hinged units 16 and 17 forming cable loops 18 and 19 and thereafter passes through the conduit into the control unit 10 and through another clamping lug 50 secured to the free end of actuating lever 11. The actuating lever is placed in its uncocked condition, the cable is pulled taut through clamping lug 50, and the cable is then clamped by means of set screws 51. The cable is thereafter placed under tension by means of tensioning unit 12 which includes a tension spring 60 coupled to actuating lever 11 through a suitable linkage 61. The other end of the spring is coupled to an over-counter tensioning lever 62 which rotates about a pivot 63. As the tensioning lever 62 rotates from its free position (shown at dotted lines in FIGURE 1A), over center to its cocked position (shown in solid lines), spring 60 places cable 14 under tension.

Actuating lever 11 can be part of a variety of different control units, preferably of the type having a latched condition which is rapidly and positively activated upon a clockwise rotation of the actuating lever. The particular unit shown in FIGURE 1 is more fully described in copending application Ser. No. 688,231, filed Dec. 5, 1967, in the name of Henry I. Flajole. This unit is designed to release a firing pin upon rotation of the actuating lever which in turn punctures a high-pressure CO cartridge 70. The escaping gas from the cartridge can be coupled via tubing 72 to directly activate a dry chemical fire extinguisher system 71, or, by means of suitable pneumatic coupling (not shown), to activate remotely located fire extinguishers of the dry chemical or other types. The unit is also designed to provide pneumatic, or electrical signals, which can be used to shut down electrical equipment, turn ,off gas valves, etc., upon detection of hazardous conditions.

1 Upon occurrence of a fire, or other hazardous conditions, sensed by the detector units, one or more of the links will separate. The leaves 21 and 22 of the associated hinged unit spread apart due to the tension on the cable and, therefore, one or more of the loops 18 or 19 substantially disappears as shown in FIGURE 4. As one of of-the cable loops disappear, there is a resulting slack in the cable. Because of the tension provided by spring 60, actuating lever 11 rotates in the clockwise direction and thereby activates the fire extinguishing system through the control unit 10.

-After the fire, or disaster, assuming damage is substantially prevented, or not too serious, the system can be easily reactivated. This is accomplished by first releasing tensioning unit 12, then cocking the control unit, replacing fusible links as necessary and then, again, placing the cable under tension by means of tensioning unit 12.

Although only one specific embodiment of the invention has been described in detail, it should be obvious to those skilled in the art that there are numerous variations within the scope of the invention, these variations including both those mentioned in the foregoing specification and those which should be obvious from the specification. The invention is more particularly defined in the appended claims.

We claim:

1. A release unit for actuating a system of the type including a tensioned cable, comprising:

a hinged member including a pivot, and a pair of relatively movable hinge leaves joined at said pivot;

means for maintaining the cable in contact with said hinge leaves with the cable passing over said pivot; and

a sensing device connectible between said hinge leaves for normally limiting the separation between said hinge leaves to form a loop in the cable as it passes over the pivot, and releasing said hinge leaves to create slack in the cable upon detection of a predetermined hazardous condition.

2. A release unit according to claim 1 wherein said means for maintaining the cable in contact with said hinge leaves comprises a sleeve attached to each of the free ends of said hinge leaves and wherein the cable slides through said sleeves.

3. The release unit according to claim 1 wherein said sensing device is a fusible link arranged to separate at a predetermined temperature.

4. The release unit according to claim 1 further comprising a generally U-shaped bracket including cable guide apertures in the legs thereof and a recess in the center portion thereof for cooperating with said pivot to center said hinged member when urged toward said recess by the tensioned cable.

5. A cable release system for use in protection against hazardous conditions comprising:

a tensioned cable adapted for connection to hazardous condition protection control unit;

a plurality of hinged units, each including a pivot,

a pair of relatively movable hinge leaves joined at said pivot, and

means for securing said cable to the free ends of said hinge leaves with the cable passing over said pivot;

a sensing device connected between each pair of hinge leaves wherein at least one of said sensing devices is a fusible link designed for separation at a predetermined ambient temperature.

7. A cable release system according to claim 5 further comprising an overcenter lever and tension spring combination secured to said cable at the end adapted for connection to the control unit for tensioning said cable.

8. In a system, the combination of a control unit adapted to actuate a fire extinguisher and including an actuating lever;

a continuous release cable anchored at one end and secured to said actuating lever at the other end; a tensioning means coupled to said other end of said cable to maintain the same under tension; and a plurality of detector units each coupled to said continuous cable and including a fusible link, each of said fusible links being connected to form a loop in said cable under normal conditions, and to release said loop upon detection of a predetermined hazardous temperature. 9. The fire extinguishing system according to claim 7 30 wherein each of said detector units further includes a hinged member with relatively movable hinge leaves and wherein said fusible links normally limit the separation between the leaves of said hinged members to form said loops in said cable.

10. In a release system, the combination of a control unit including an actuating lever;

a continuous release cable anchored at one end and secured to said actuating lever at the other end; a tensioning means coupled to said other end of said cable to maintain the same under tension; and at least one detector unit coupled to said cable to form a loop in said cable under normal conditions, and to release said p upon detection of a predetermined condition so that the resulting slack in the cable actuates said control unit.

References Cited UNITED STATES PATENTS 1,508,376 9/1924 Adams 16942 1,953,582 4/1934 Belknap 169-42 2,730,900 1/ 1956 Rowley 16942 3,195,648 7/1965 Atack 169-42 EVERETT W. KIRBY, Primary Examiner US. Cl. X.R. 169-2, 9, 26 

